Chiropractic experience and medical evidence has shown that the actual physical posture adopted by a person, when either seated or standing, can have a significant influence on the overall comfort, and ultimately the health, of that person. Correct posture, when either standing or seated, will minimise the likelihood of onset of complaints associated with incorrect posture, as for example muscular soreness and tension, etc. In turn, and especially in a work environment, output can be expected to be improved, or at worst more easily maintained at a desired level.
In the past numerous attempts have been made to provide a seating arrangement or chair assembly, in particular, which lends itself to ready adjustability to suit the requirements of any particular user. Almost invariably, however, such prior art arrangements have suffered from the disadvantage in that the degree of adjustability provided is limited and, more importantly, the types of adjustment or adjustability afforded have been even further restricted. In the result the prior art arrangements in general made scant provision for the differing physical or physiological dimensions of all possible or potential users and did not afford adjustability to suit all possible requirements.
By way of further explanation of the above, in any seating arrangement the actual posture adopted by the user is dependent to a significant extent first of all on the physical or physiological requirements of the user, and secondly on the personal whims of such user. To cater for all potential situations it would be necessary to provide for ready adjustment of such parameters as:
(i) the angle to the vertical of what might be termed the back-rest portion or member of the chair assembly; PA0 (ii) the angle of the preponderant horizontal seat portion or member; PA0 (iii) the height of the arm-rests above the seat portion or member; PA0 (iv) the height of the seat portion or member above ground level, to cater for different leg-lengths or preferred knee lengths; PA0 (v) lumbar support or contour adjustment in the back-rest portion or member to cater for different body lengths and shapes; PA0 (vi) both horizontal and vertical adjustments of a head rest to cater for different body shapes and usage requirements; and PA0 (vii) the front-to-back dimension of the seat or in other words the seat depth.
Prior art arrangements have not allowed for adjustment of all the aforementioned parameters.